Oral health-related quality of life (OQOL) concerns the impact of oral health on the social and psychological well-being and the daily functioning of children and their families. Although several measures of OQOL exist for use with adults, there are no comparable measures of children. This project will develop a set of measures of pediatric oral health-related quality of life (POQOL), suitable for use with children and adolescents, that assesses the impact of oral health on both children and their families. To accomplish this task, the following aims are proposed: 1) Develop, refine and validate a measure of OQOL for use with children and adolescents; 2) For each of the four age-appropriate versions of the OQOL instrument, develop a comparable Spanish-language version; 3) Conduct further validation of all English and Spanish instruments to assess their sensitivity to change over time to responsiveness to interventions; 4) Combine the POQOL assessment with other clinical, demographic and psychosocial measures to explore potential sources of disparities in oral health; and 5) create a short version of the POQOL measures for screening purposes. Patient focus groups will aid in item development and pre-testing of measures. Reliability will be determined through re-testing, and validity by examining the relationship between POQOL and established measures of pediatric health and health-related quality of life. Regression analyses will be used to examine the relationship between POQOL, psychosocial factors and oral health disparities in children. The resulting POQOL measures will be used in analyses of data collected by other projects in this Program Proposal, and more generally can be used to assess oral quality of life in population surveys, as outcome measures in clinical trials, and in clinical practice to evaluate the impact of interventions.